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484

answers:

4

I did some of my own research and found out that SID-chips had only few hardware supported synthesizing features. Including three audio oscillators with four possible waveforms (sawtooth, triangle, pulse, noise), with ADSR audio controls and ring modulators. Accompanied with oscillator sync and ring modulators. Also read there was a way to play single PCM sound as well.

It is all so little, but still I heard lots of different sounds from my TV sets. How were they combined to produce all that variety of audio?

To give some specifics, I'd like to know how to combine those components to produce guitar, piano or drum -like audio? Another interesting things would be different buzzes and sounds specific to C64.

+1  A: 

Check out some of the C64 emulators out there. I've read that some of them are 100% accurate in ther sound reproduction, true to the original.

Neil N
none are 100% accurate. If you compare the originals and the emulated counterparts,you can definitely hear a difference.
Toad
+2  A: 

Take a look at some of these docs related to producing music on the C64:

http://sid.kubarth.com/articles.html

Brandon E Taylor
+12  A: 

I used to write music on the C64 for games, demos and even services (I wrote the official QauntumLink theme, even). As for your question, the four different waveforms were typically overlaid with the sync and ring mods (less often ring, because it was unpredictable on different versions of the SID chip), and sometimes used cleanly.

For example, a typical 'snare' sound would be composed of a noise waveform with a very fast attack and sustain, and depending on whether you wanted a drumstick or brush sound, either a very fast decay and moderately short release, or a short decay and slower release.

Getting the right sound was typically trial and error, and the limitations were pretty heavy. You really never got to the point of piano or guitar sound due to the simple waveforms without overlayable harmonic waveforms, about the best you could get was things that sounded beepy, things that sounded marimba-y, and things that sounded like a snare drum.

One of the tricks used most often to extend sound was done with fast machine code playback routines that could change the played notes on voices so quickly as to give the impression of a fuller, harmonic tone. We just called it arpeggiation, although at 10 to 12 note changes a second it sounded more like a buzzy chord.

As for the sampled waveforms, they were only available as single bit and later 4 bit samples. These sounded terrible despite our best attempts, because basically the method of playback for a sample on the 64 was to play a white noise waveform and rapidly alter the volume on the SID chip to produce a rising and falling wave. Do it fast enough and it sort of sounds like the original sound, poorly tuned in on a staticky radio.

I suggest you grab hold of a C64 emulator for the PC (CCS64 is a good one) and a 64 BASIC programming guide and just play around.... the SID chip is entirely manipulatable from BASIC.

To sum up, how did we get all of those piano and guitar sounds on a C64? We didn't, really.

Zenham
The best tune I've ever heard (on my C-64) was the one playing in the background of the game 'Super Cycle' :) I'm still looking for the mp3 :)
Ryan Fernandes
@ryan fernandes look no further: http://www.6581-8580.com/
Toad
+2  A: 

This type of music you are describing falls into the category of "chiptunes". I'd recommend checking out some modern trackers like MilkyTracker, which are used to create music in this style. There are libraries like libmodplug that allow you to play tracker in your software.

John Cromartie